If you don't have an FBV MkII controller, that means you cannot update the firmware in the amp (the Infusion update of several years ago has to be downloaded and installed in the amp). These controllers also give you access to Spider Edit - being able to edit your sounds on the computer, and save them to your amp, and to download preset patches from other users.

A controller like the Express or Shortboard also gives you some other options - changing presets on the fly, and wah/volume pedal (and more with the shortboard - being able to turn on/off certain parameters).